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5 Stream Processing for Wireless Systems

Until now, most research in stream processing has addressed media and scientific applications. Wireless communication in forms such as cellular telephony systems and local and personal area networks has become a ubiquitous part of modern life. Mobile wireless systems have relatively high demands for processing and power efficiency and represent a new domain in which stream processors could be quite useful. With around one billion cell phones sold annually, the volume in this market provides economic justification for the development of specialized processor architectures. We present a brief overview of cellular communication technology and indicate avenues for the application of stream processors.

First generation (1G) cellular systems using analog technology were introduced in Scandinavia in 1981 and were followed by similar systems in the United states. They provided only voice transmission. The first digital cellular systems that made their appearance in 1990 and were termed second generation wireless (2G) systems. They provided better voice quality and added data services support with transmission rates up to 9.6kbits/s. To support high data rates and to be able to provide multimedia services anytime and anywhere, the International Telecommunications Union defined a family of systems for the third generation (3G) mobile telecommunications called IMT-2000. The 3G system provides data rates up to 2 Mbits/s for stationary users, 384 Kbits/s for pedestrians, and 144 Kbits/s for vehicular users. The services offered by 3G systems can be divided into different classes depending on their delay sensitivity. Voice, video telephony, and video games are delay sensitive. Email, short message service, and data downloads are not delay sensitive. In this article, we explain the Wide-band Code Division Multiple Access (WCDMA) system that is commonly used in 3G systems.

The quest to improve data rates and quality of service and to provide seamless roaming and global mobility for voice and data services, a new wireless standard (4G) is currently being formulated. The technologies that would most likely play an important role in 4G are Software Defined Radio (SDR) and Multiple Input Multiple Output (MIMO) antenna systems. 3G and 4G systems consist of several layers each providing a specific function. The following sections will only focus on the physical layer where all the compute intensive algorithms are located.


next up previous contents
Next: 6 WCDMA Physical Layer Up: Stream Processors and their Previous: 4.3 The Cell   Contents
Binu K. Mathew, Ali Ibrahim